Q regarding shift extension & N20 on an A4
Thread Starter
Joined: Nov 2003
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From: St. Louis, MO
Q regarding shift extension & N20 on an A4 From what I understand, a bigger and/or looser stall will have a higher shift extension which usually equals to a higher mph NA (mods, weight permitting). What I don't understand, when spraying a decent shot of n20 (150+) on a loose converter, too high of an shift extension will blow through the converter causing mph loss. How come a higher shift extension benefits for NA, but hurt N20? 
the shift extension is determined by the torque inputed into the converter. I car making say 400 # of torque may shift at 6500rpm and fall back to 5800 for a shift extention of 700 rpm. Now the same converter on say a 200 shot will have a much lower shift extension and only drop in rpm down to say 6200 rpm and have a low efficiency. A converter in a highly modified car may be just right, the same converter in a stock car would be way to tight.
Thread Starter
Joined: Nov 2003
Posts: 834
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From: St. Louis, MO
Is it a "lower" shift extension? I said "higher" shift extension in my first post, but I guess it's a lower shift extenstion (lesser drop in rpm between shifts). So, if the rpm drops around 900 rpm from the shift on N20 (6600ish to 57K), would that consider to be "not" blowing through the converter and efficient? Could you loose mph from a low shift extension NA? I'm trying to figure all of this out, because I'm not getting hardly any mph on n20 whatsoever. 
If your dropping from 6600 to 5700 it doesnt sound like your blowing through the converter. If you are seeing poor gains are you sure you dont have a tuning issue. What size shot are you running and what where your gains? what is your shift extension on motor?
Thread Starter
Joined: Nov 2003
Posts: 834
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From: St. Louis, MO
I was using the 6600 to 57k as an example. I also swapped converters. Rpm drop with the 3400 stall n/a was around 4900-5k. Around 55k on N20. 3800 stall n/a was around 53-54K. I'm not sure on N20. This was on a 150 shot. Check out the first page from my thread when you get a chance:
https://ls1tech.com/forums/showthrea...917&highlight=
https://ls1tech.com/forums/showthrea...917&highlight=
